A side airbag device for protecting an occupant from an impact particularly during a side collision is generally installed in a window-side side interior of a backrest of a seat (hereinafter, referred to as a seat back).
The side airbag device is configured such that, during a side collision, an inflator is operated by an output signal transmitted by a sensor having detected an impact and generates gas to deploy an airbag between an inner-side surface of a vehicle and an occupant.
There are side airbag devices configured as described above which are installed with a tether that assists guidance of a deployment direction of an airbag when the airbag is being deployed (for example, Japanese PCT Application No. 2007-510581).
In the side airbag device disclosed in Japanese PCT Application No. 2007-510581, a tether is attached to an interior of the airbag. For example, a configuration is adopted in which a rear edge of the tether is attached to a rear end side of the airbag and, at the same time, a front edge of the tether is joined to one sheet of base fabric at a location in proximity of a front end side of the airbag.
Moreover, the rear end side of the airbag refers to a portion which constitutes a rearward side of the vehicle when the airbag is deployed. In addition, the front end side of the airbag refers to a portion which constitutes a forward side of the vehicle when the airbag is deployed.
In the case of the side airbag device disclosed in Japanese PCT Application No. 2007-510581, as the airbag is inflated, the airbag is pulled by an action of the tether and expands adjacent to a side surface of the vehicle to the forward side of the vehicle.
With the side airbag device disclosed in the above-referenced document, a tether provided in the interior of the airbag is capable of controlling the deployment direction of the airbag. However, the tether does not have a function of holding the airbag at a deployed position after the airbag is deployed.
A problem to be solved by the present invention is that, while the tether provided in the airbag of the side airbag device disclosed in the above-referenced document is capable of controlling the deployment direction of the airbag, the tether does not have a function of holding the airbag at a deployed position after the airbag is deployed.
An object of the present invention is to solve the problem described above and equip a tensioned tether provided for an airbag with a function of holding the airbag in a desired deployed position after the airbag is deployed.